RSTU is a rectangle which has a breadth of 10 cm. It is divided into 4 triangles. Triangle V is
111 of the area of the rectangle and
13 the area of Triangle X. Triangle W has an area of 25.5 cm
2.
- Find the area of the rectangle.
- Find the perimeter of the rectangle.
V |
W |
X |
Rectangle |
1 |
|
|
11 |
1 |
|
3 |
|
1 u |
1.5 u |
3 u |
11 u |
(a)
Area of Triangle W
= Half of Rectangle RSTU - Triangle X - Triangle V
= (11 u ÷ 2) - 1 u - 3 u
= 1.5 u
1.5 u = 25.5
1 u = 25.5 ÷ 1.5 = 17
Area of the rectangle
= 11 u
= 11 x 17
= 187 cm
2 (b)
Length of the rectangle
= 187 ÷ 10
= 18.7 cm
Perimeter of the rectangle
= 18.7 x 2 + 10 x 2
= 57.4 cm
Answer(s): (a) 187 cm
2; (b) 57.4 cm